1. Field of the Invention
The present invention relates to cases for electric pocket lamps or flashlights energized by batteries.
2. Description of the Prior Art
It is more and more conventional to substitute for metal pocket flashlight cases, cases formed of plastics material in order to overcome the drawbacks inherent in the former. In fact, on the one hand, poor operation was generally due to poor contacts or poor insulation of certain elements; on the other hand, metal cases were often deteriorated by rapid oxidation caused by the decomposition of discharged batteries that they contained at the end of a certain period of non-use. If the use of plastics materials has been able to remedy the second drawback mentioned, the presently known constructions still use the same type of contact, consisting of placing each of the terminals of the battery in permanent connection with a flexible metal strip of which on end is at the tip of the base of the flashlight bulb and the other is urged against the cylindrical portion of the socket by elastic deformation under the effect of a push-button movable in translation, thus closing the electrical circuit. These contact strips are either incorporated in the mold before the injection of the plastics material, or introduced, after unmolding the case, into housings provided for this purpose. Both of these methods of manufacture have the drawback of being costly and often of being deteriorated in the areas of implantation of the contact strips by reason of the variation in elasticity of plastics materials under the influence of low temperature or of ageing.
To avoid the presence of contact strips, U.S. Pat. No. 1,404,077 provides a removable battery in the case of an electric flashlight. The battery-bulb electrical circuit is closed or opened by actuating an external push-button on the case which permits the battery to be moved axially in order to bring the stud of the battery into contact or out of contact with the base of the bulb. Such a system being designed only for cylindrical batteries, and not being provided in any way for forming from plastics material, it does not resolve the above-mentioned problems.
Pocket flashlights are also known such as those described in French Pat. No. 69 16,548, which include a onepiece part for fixing the illuminating head as well as the housing of the bulb, said part being formed of an electrically insulating material. This French Pat. No. 69 16,548 describes pocket flashlights provided only for cylindrical batteries and in addition including two metal pins 7 and 9 and a switch device provided with a strip in contact with the pole of the battery opposite the stud of said cylindrical battery and coming into contact with one of the pins.
Pocket lamps according to the French patent mentioned have a complex assembly and are costly to manufacture.
It is an object of the present invention to provide a case which enables all of the above-described drawbacks to be avoided, limiting the number of metal parts entering into its construction to one, which part, if necessary, can easily be replaced in the case of deterioration.